Improved Avena Coleoptile Elongation Test for Auxin'
نویسنده
چکیده
Sum rv01,1f. A mo(lifie(l )rocedlure is presente(d for the bioassay of aulxin lusilng -Iv'eno coleoptile segments. The modifications introduicedl restult in a substantial improvement of the commonly uised( coleoptile elongatioil tests. The proposed test retains the simplicity of physical reqillremeints and of manipulatioIn characteristic of all elongatioln tests. The maiin featuire of the proposed test is that it permits the measurement of the elongationi of coleoptile segments as being directly proportionial to the conicenitratioin rather thain to the logarithm of the concenitration of indoleacetic aci(l. WN-ith an accuracy andl a range comparable to those of the staindard Avcnoa curvature test, the proposed bioassay overcomes the limitations for the quantitative assessment of aulxin inhereint in other coleoptile eloingatioin tests. AIn additional advantage is prov(ided by the present coleoptile can 1)e ultilized thuis donbl)ling the gTiVen nutmmber of coleoptiles.
منابع مشابه
Some Effects of Decapitation on Electrical and Elongation Phenomena in the Avena Coleoptile.
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The action of auxin in the promotion of growth has been suggested in the literature to depend on cell wall acidification. In a former investigation by the present authors the electrochemical balance in auxin-induced proton extrusion was shown to be maintained by potassium net uptake. The present paper reports data demonstrating that the elongation of Avena coleoptile segments is accompanied by ...
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